/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Diagnostics
 *
 * The Initial Developer of the Original Code is
 * Ryan Flint <rflint@dslr.net>
 * Portions created by the Initial Developer are Copyright (C) 2006
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

// Contains helpful functions accessible to the main app and tests

var mozDiagHash = {

  /*
   * @param aStream An XPCOM file stream
   * @param aType The type of hash to be calculated. e.g. SHA256
   * @return The computed hash as binary data
  */
  rawFromStream: function (aStream, aType) {
    var hashService = Cc["@mozilla.org/security/hash;1"].
                      getService(Ci.nsICryptoHash);
    hashService.initWithString(aType);
    hashService.updateFromStream(aStream, aStream.available());
    return hashService.finish(false);
  },

  /*
   * @param aStream An XPCOM file stream
   * @param aType The type of hash to be calculated. e.g. SHA256
   * @return The computed hash as an ASCII string
   */
  asciiFromStream: function (aStream, aType) {
    var raw = this.rawFromStream(aStream, aType);
    return this.toHex(raw);
  },
  
  /*
   * @param aString A string
   * @param aType The type of hash to be calculated. e.g. SHA256
   * @return The computed hash as binary data
   */
  rawFromString: function (aString, aType) {
    var data = [];
    for (var i = 0; i < aString.length; i++) {
      data.push(aString.charCodeAt(i));
    }
    
    var hashService = Cc["@mozilla.org/security/hash;1"].
                      getService(Ci.nsICryptoHash);
    hashService.initWithString(aType);
    hashService.update(data, aString.length);
    return hashService.finish(false);
  },

  /*
   * @param aStream A string
   * @param aType The type of hash to be calculated. e.g. SHA256
   * @return The computed hash as ASCII data
   */
  asciiFromString: function (aString, aType) {
    var raw = this.rawFromString(aString, aType);
    return this.toHex(raw);
  },

  /*
   * @param aRawData Binary data
   * @return ASCII hex representation of the binary data
   */
  toHex: function (aRawData) {
    var chars = '0123456789ABCDEF';
    var hex = new Array(aRawData.length * 2);
    for (var i = 0; i < aRawData.length; ++i) {
      hex[i * 2] = chars.charAt((aRawData.charCodeAt(i) >> 4) & 15);
      hex[i * 2 + 1] = chars.charAt(aRawData.charCodeAt(i) & 15);
    }
    return hex.join('').toLowerCase();
  }
};